Grinding-mill



0. SIMPSON. GRINDING MILL (No Model.)

No. 423,704. Patented Mar. 18, 1890.

mlllllllllllllllllllll llllll Z L Z UNITED STATES PATENT OFFICE.

ORVILLE SIMPSON, OF COLLEGE HILL, OHIO.

GRINDING-MILL.

SPECIFICATION forming part of Letters Iatent No. 423,704, dated March18, 1890.

Application filed October 21.1889.

To all whom it may concern.-

Be it known that I, ORVILLE SIMPSON, a citizen of the United States,residing at Ool lege Hill, in the county of Hamilton and State of Ohio,have invented certain new and useful Improvements in Grinding-lvlills,of which the following is a specification.

' .My invention relates to the class of grinding-mills in which theoperating burrs or stones are mounted one above the other within asuitable frame, the running-burr being mounted on a vertical spindle,which is supported by a-bridge tree and pivotal lighterbar and providedwith regulating devices whereby the said stones may be run a greater orless distance apart, as desired; and my invention consists in theconstruction and arrangement of safety devices, all as hereinafter fullydescribed, and particularly pointed out in the claims.

In the accompanying drawings, Figure l is a central sectional elevationof a grindingmill with my presentimprovements (described and claimedherein) applied thereto, the curb or casing usually around the burrsbeing omitted; Fig. 2, a vertical section, partly. in elevation ,of myimprovements complete, showing the bridge-tree and lighter-bar brokenoif Fig. 3, a transverse sectional elevation on line as 00, Fig. 2; andFig. 4., a broken longitudinal elevation of the lighter-bar, showing itsouter or free end, which engages my improved dev1ce.

v A represents the uprights, and A the connectingirders or cross-beams,which together form the usual frame of an ordinary grinding-mill.

B represents the upper or stationary'burr, and O the lower or runningburr, of the mill shown in the drawings. Both said burrs may besupported andincasedin any desirable manner, the lower or running onebeing suit-ably mounted upon and connected with a tapered spindle orupright shaft D, so as to revolve therewith, and said shaft beingproperly journaled at its upper and lowerends, as custom. ary ordesired. 7

a a, are the customary bevel driviug gears, the driven one a being keyedto spindle D, and the driver a to the horizontal shaft b.

E represents the bridge tree, supported at. its ends by the girders Aand F the lighter a No. 327,629. (No model.)

ing pivotally connected at one end to the bottom thereof. The saidhorizontal shaft 1) is journaled in the lighter-bar intermediate theends of the latter, as clearly shown in Fig. 1 and as usual. I

G represents a hollow post or stand-pipe mounted upon one end of thebridge-tree, andc the usual regulating screw or rod for the adjustmentof the running-stone. Saidregulating-screw passes upward through anaperture or slot G in the bridgetree and the hollow of said post toreceive a hand-wheel or Y 1 bar located directly under the bridge-tree,be!

nut d on its upper screw-threaded'end, and

also an elasticrubber cushion or spring e,-

which latter fits loosely upon said screw intermediate the central hubof said hand-Wheel and the top of said post.

c is a loop or stirrupformed at thelower end of the regulating-screw o,and a represents the lower cross-baror ligament of said stirrup, uponwhich the outer or free end of the lighter-bar has heretofore rested forsupport at all times, both while the burrs were running close togetherand thrown apart.

f is a notch in the lower edge of the said outer end of the lighter-bar.

H represents a transverse j frangible pin, whose ends fit Withinsuitable openings made in the enlarged portions h of the vertical sidesof stirrup c, slightly above the said crosspiece 0', and provided tosupport the notched free end of the lighter-bar, in the manner and forthe express purpose immediately hereinafter described. The pinH is anauxiliary one in connection with said cross-piece c, and is preferablymade of wood of sufficient strength to normally-bear theweight of theparts supported by the lighter-bar and to withstand the resistance orstrain incident to the ordinary grinding of the mill on grain, but whichimmediately yields or breaks on the entrance of any hard foreignmatter-such as stones, bolts, nuts, or the like-between the burrs,thereby causing therunningstone to continue to rotate a suitabledistance apart from its companion burr to permit the said foreign matterto escape or be removed from between said burrs, thus preventing anyfurther material injury to the grinding surfaces of either of saidburrs.

In. the operation of my device the free end of the lighter-bar dropsinstantly on the rupt-- ure of the auxiliary pin Hand is at once caughtby the cross-piece c" of the stirrups 0', its notch f engaging saidcr0sspiece in the usual manner. The mill may continue to grind after thebreaking of pin H by merely turning the hand-wheel to raise theregulating-screw and the lighter-bar,with the grinding devices, totheirformer positions, and the rubber cushion or spring 6, abovedescribed, used to operate singly in connection with the burrs andpermit them to part sufficiently for the escape of any foreign mattershould an unusual'strain, caused by any such resistless foreign matter,accidentally enter between them.

It is obvious that both the wood en-pin and elastic spring-cushion e canbe used together in connection with the grindingdevices, as

pivotal lighter-bar, vertical spindle, burrs f and O, regulating-screwc, hand-wheel 01-} I101- ,low post or cylinderG,:l-oop or stirrup c at 1lower end of said regulatingescrew, transverse bar a" of said stirrup,break-pin H, mounted in said stirrup slightly above said. transversebar0", and" cushion or springs, mounted'on' the upper end ofsaidregu'lating-screwf interj mediate the top of said hollow-postandhandwheel, substantially as and for the purpose herein shown anddescribed, or they may be used orapplied separately, as desired; but theformer-combination I deem the better,.forthe reason thatshould the pinbreak the mill need not necessarily be stopped to renew said pin, but itmay go on grinding and the hand-wheel beturned so as to bring therunning-burrinto work-ingposition, the said elastic cushion theirpresenting a sufficiently yielding bearing or support to permit theescape of foreig-nmatter should any enter between the" burrs,aszpreviously stated herein. It isialso" obvious that; instead of usinga rubber cushion on the regulating-screw,ias shown, a, spira'l springcould be substituted and the device operate quite aswell;

I claim 1. In ag-rinding-rnill, the combination, with E the pivotallighter-bar, vertical spindle, burrs B and O, and verticalregulating-screw c, the

latter being passed upward through a cylinder or hollow post G andengaged by an adjusting hand-wheel d on its upper threaded end, of atransverse break-pinH, mounted in the stirrup or loop c'at the lower endof said regulating-screw, and cross bar a", forming in the manner andfor the purpose specified. 2. The regulating screw or rod 0, having atits lower end aloop or stirrup c, cross-bar c", a forming the bottom ofsaid stirrup, and transverse break-pin H, mounted in said stirrup bar,substantially as and for the" purpose specified.

3. In a grinding-mill, thev combination of a In testimony'of whichinvention I' h'av'e here Witnesses:

JOHN E. J ONES, FRANK L. MILLWARD;

45 thebottom of said stirrup, constructed, ar-

ranged, and adapted to operate substantially *parallel with and slightlyabove said cross-

